I must admit that the best one is yours, followed closely by sq1vga one. The worst is absolutely sq5 one. No sane man would walk that way! 
That said, I feel some sort of incoherence between how realistic the sprite is and how cartoon-ish the walk-cycle looks.
It reminds me a lot of this one:
http://youtu.be/e2pTt_7AjzM
It's a cool walk animation, but somehow unrealistic, so if you aimed at realism, you should make it less "dynamic" if you get what I mean.

That said, I feel some sort of incoherence between how realistic the sprite is and how cartoon-ish the walk-cycle looks.
It reminds me a lot of this one:
http://youtu.be/e2pTt_7AjzM
It's a cool walk animation, but somehow unrealistic, so if you aimed at realism, you should make it less "dynamic" if you get what I mean.